[ale] MySQL help

David S Jackson deepbsd.ale at gmail.com
Fri Mar 13 13:52:09 EDT 2015


I'm a MySQL newbie.  I'm just starting to use Python to talk to MySQL 
databases, but first I need to understand the MySQL query language!

So, I have two tables:  (zoo) animal and food.

animal has the columns ID, NAME, FAMILY, WEIGHT

food has  ID, ANIMALID, FEED

So if I go: select id, name, family, feed from animal JOIN food ON 

I get something like:

ID   NAME        FAMILY      FEED
1    Seymore   Snake        mice, leaves
2    Gerard      Giraffe       leaves, grass

So, if I have a situation where I want to see whether an animal has been 
added the animal table but may have not been added to the food table, 
how would I compose that query?

That is, the animal could have been added to the animal table and could 
get an id, say 10, but the food table could have 20 foods already 
entered and the animal-id would be used several times.

I was thinking, is there a way I can ask, "does the highest animal.id 
number equal the highest food.animalid number"?  If not, what animal is 
not getting fed?


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